My computer, running XP pro, will no longer go to sleep as of tonight. The monitor will go black for like one second after the time period of inactivity is up, but then it will come right back on. I had installed a freeware screensaver earlier that day but I uninstalled it right after. Perhaps that messed something up on my system. I've checked but I can't seem to find any mention of it left on my computer. Is there anything I can do to get it to sleep again, short of reinstalling windows.